Add Cython build infra + initial extension module #77

Job	Run time
Docs, Examples, and Eval	14m 0s
Conda Python 3.10 on macos-latest	18m 58s
Measure Cython Coverage	6m 56s
Conda Python 3.10 on macos-14	10m 1s
Minimal Supported Dependencies	7m 3s
Conda Python 3.10 on windows-latest	11m 29s
Conda Python 3.10 on ubuntu-latest	16m 6s
Vanilla Python 3.10 on windows-latest	11m 53s
Conda Python 3.11 on macos-latest	11m 38s
Vanilla Python 3.10 on ubuntu-latest	10m 8s
Conda Python 3.11 on macos-14	15m 30s
Vanilla Python 3.10 on macos-14	6m 16s
Conda Python 3.11 on windows-latest	13m 0s
Vanilla Python 3.11 on windows-latest	12m 51s
Conda Python 3.11 on ubuntu-latest	16m 26s
Vanilla Python 3.11 on ubuntu-latest	9m 54s
Vanilla Python 3.11 on macos-14	6m 14s
Test Suite Results	17s
	3h 18m 40s

Provide feedback